反应详情

温度

90 °C

To a mixture of 6,7-dichloro-1H-indole-2,3-dione (4.95 g) in 25 mL glacial acid and 25 mL acetic anhydride was added chromium (VI) oxide (3.9 g, 39 mmol) portionwise at 85° C. After addition, the mixture was stirred at 90° C. for 30 min. and cooled down to room temperature. Filtration provided a small amount of 7,8-dichloro-1H-benzo[d][1,3]oxazine-2,4-dione. Evaporation of the filtrate gave the majority of the product as a green solid containing chromium (III) oxide.

1. additionAfter addition
2. temperaturecooled down to room temperature
3. filtrationFiltration